It is perhaps noteworthy that, for the first year of the Transformers franchise, the bad guys were outnumbered by the good guys roughly two-to-one! While I can't speak to how well that ratio has held up in other eras of the franchise, having more Autobot (good guy) figures than Decepticons (bad guys) has definitely been a recurring reality throughout the years. Indeed, on the assumption that kids don't want to buy "bad guy" toys, there are whole years of the Japanese line where Deceptions are all but absent altogether! I can't say I've ever quite gotten my head around that assumption myself. As a sometime-actor in grade school and college, I know that role-playing as bad guys can be tons of fun! As one of the best-remembered bad guys from the early years of the Transformers franchise, it's hard to imagine kids not wanting to have a Rumble figure of their very own!
Let's get the alt-mode out of the way first. Rumble was one of several Decepticons that turned into microcassette tapes. Kids nowadays probably have no idea what this is, outside of a funny-colored rectangle, but cassette tapes were in wide usage during the 1980s, and Transformers that turned into cassettes were almost always popular. That said, cassette tapes admittedly don't make for very exciting photographs!
So let's move on to Rumble's robot mode (using the recent Japanese "Masterpiece" version of the character for demonstration purposes*). Rumble is a red-and-black robot, at least, in the original version and most subsequent official depictions over the years. However, this is admittedly at variance with the 1980s cartoon, which made a mistake late in the start-up process and switched Rumble's color scheme with something more closely resembling his same-mold twin Frenzy (about whom I'll have more to say in coming weeks). This has led to one of the most long-standing debates within the Transformers fandom, often shorthanded along the lines of FIRRIB, short for "Frenzy is Red, Rumble is Blue" (after the cartoon depiction), although several other permutations are out there, depending on the fan's preference. My own preference is that the cartoons made a mistake (ably demonstrated by noting that the cartoon "bible" itself has a note calling Rumble a "red robot"), and I'm actually kind of annoyed that after being consistently red in toy form for over 25 years, Hasbro has recently started to cave to the cartoon's disproportionate popularity, and has started releasing (or, in one case, planned to release) blue Rumble toys these past couple of years (although I'm pleased to learn that the recent Toys R Us exclusive American re-release of this same toy maintains the "Rumble is Red" identity).
Rumble's most distinctive feature is the one from which he gets his name. Rumble can cause earthquakes! In the cartoon, this was famously depicted by having Rumble's arms turn into massive pistons with which he would pound the ground. The original toy had no such pistons, even as accessories, and so other depictions had Rumble create earthquakes differently (the comic suggested that Rumble sent vibrations through his legs, for example). However, the cartoon's pistons quickly became rather iconic, and so it was no surprise to see them depicted in toys as the character came back in other forms over the years. Rumble is now fully equipped for maximum destruction!
*Thanks to my brother Nick, for the generous use of his Masterpiece Rumble figure while we were on vacation visiting him and the rest of my family this past week. Nick also helped set up lights to make this photo shoot a success. I do apologize to those of you who have perhaps noticed the very slight transformation error. I discovered after completing the photo shoot that this toy allows you to extend Rumble's torso upward slightly to reveal a bit of a red abdomen, in keeping with the Rumble/Frenzy animation model. The decision not to take up more of our vacation time to retake the relevant photos was mine and mine alone.